Vehicle speed control using speed maps

ABSTRACT

Disclosed is a method for controlling the speed of a vehicle, the method comprising: determining a speed limit; determining an offset value based on (i) the speed limit, and (ii) a speed map, the speed map comprising a plurality of entries, each entry associating one of the offset values with a respective speed limit; and setting the speed of the vehicle according to the speed limit and the determined offset value.

TECHNICAL FIELD

The present disclosure relates generally to vehicles. In particular,embodiments of the present disclosure relate to controlling the speed ofa vehicle.

DESCRIPTION OF RELATED ART

Modern vehicles include many convenience features to control or assistcontrolling the vehicle. One such feature is often referred to as“cruise control.” With this feature, the driver may select a particularspeed to be maintained by the vehicle. The vehicle then maintains thatspeed until the driver changes the speed, or disables cruise control,for example by turning the feature off or pressing the brake pedal.

BRIEF SUMMARY OF THE DISCLOSURE

In general, one aspect disclosed features a method for controlling thespeed of a vehicle, the method comprising: determining a speed limit;determining an offset value based on (i) the speed limit, and (ii) aspeed map, the speed map comprising a plurality of entries, each entryassociating one of the offset values with a respective speed limit; andsetting the speed of the vehicle according to the speed limit and thedetermined offset value.

Embodiments of the method may include one or more of the followingfeatures. Some embodiments comprise modifying the speed map according tobehavior of a driver of the vehicle. In some embodiments, modifying thespeed map occurs without human intervention. In some embodiments,modifying the speed map occurs responsive to human intervention. In someembodiments, modifying the speed map comprises: measuring a speed of thevehicle; and recording the speed limit and an offset value in the speedmap, the offset value representing a difference between the speed of thevehicle and the speed limit. Some embodiments comprise determining anadverse condition for the road being traveled by the vehicle; andadjusting the speed of the vehicle based on the adverse condition. Insome embodiments, determining an offset value comprises: when the speedmap does not contain an entry for the determined speed limit,interpolating using a plurality of the entries in the speed map.

In general, one aspect disclosed features a method for controlling thespeed of a vehicle, the method comprising: determining a speed limit;determining a desired speed based on (i) the speed limit, and (ii) aspeed map, the speed map comprising a plurality of entries, each entryassociating one of the desired speeds with a respective speed limit; andsetting the speed of the vehicle according to the speed limit and thedesired speed.

Embodiments of the method may include one or more of the followingfeatures. Some embodiments comprise modifying the speed map according tobehavior of a driver of the vehicle. In some embodiments, modifying thespeed map occurs without human intervention. In some embodiments,modifying the speed map occurs responsive to human intervention. In someembodiments, modifying the speed map comprises: measuring a speed of thevehicle; and recording the speed of the vehicle and the speed limit inthe speed map. Some embodiments comprise determining an adversecondition for the road being traveled by the vehicle; and adjusting thespeed of the vehicle based on the adverse condition. In someembodiments, determining a desired speed comprises: when the speed mapdoes not contain an entry for the determined speed limit, interpolatingusing a plurality of the entries in the speed map.

In general, one aspect disclosed features non-transitorymachine-readable storage medium encoded with instructions executable bya hardware processor of a computing component of a vehicle, themachine-readable storage medium comprising instructions to cause thehardware processor to: determine a speed limit; determine an offsetvalue based on (i) the speed limit, and (ii) a speed map, the speed mapcomprising a plurality of entries, each entry associating one of theoffset values with a respective speed limit; and set the speed of thevehicle according to the speed limit and the determined offset value.

Embodiments of the non-transitory machine-readable storage medium mayinclude one or more of the following features. Some embodiments compriseinstructions to cause the hardware processor to: modify the speed mapaccording to behavior of a driver of the vehicle. Some embodimentscomprise instructions to cause the hardware processor to: modify thespeed map without human intervention. Some embodiments compriseinstructions to cause the hardware processor to: modify the speed mapresponsive to human intervention. Some embodiments comprise instructionsto cause the hardware processor to: measure a speed of the vehicle; andrecord the speed limit and an offset value in the speed map, the offsetvalue representing a difference between the speed of the vehicle and thespeed limit. Some embodiments comprise instructions to cause thehardware processor to: determine an adverse condition for the road beingtraveled by the vehicle; and adjust the speed of the vehicle based onthe adverse condition.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure, in accordance with one or more variousembodiments, is described in detail with reference to the followingfigures. The figures are provided for purposes of illustration only andmerely depict typical or example embodiments.

FIG. 1 illustrates an example vehicle in which embodiments of thedisclosed technology may be implemented.

FIG. 2 illustrates an example architecture for controlling the speed ofa vehicle in accordance with one embodiment of the systems and methodsdescribed herein.

FIG. 3 is a flowchart illustrating a process for controlling the speedof a vehicle using offset speeds according to one embodiment.

FIG. 4 shows an example speed map storing offset speeds according to oneembodiment.

FIG. 5 is a flowchart illustrating a process for controlling the speedof a vehicle using desired speeds according to one embodiment.

FIG. 6 shows an example speed map storing desired speeds according toone embodiment.

FIG. 7 is a flowchart illustrating a process for learning a speed mapaccording to one embodiment.

FIG. 8 shows a speed map using adverse conditions offsets.

FIG. 9 shows an example computing component according to variousembodiments.

The figures are not exhaustive and do not limit the present disclosureto the precise form disclosed.

DETAILED DESCRIPTION

Various embodiments are directed to allowing a driver to set vehiclespeed relative to the legal speed limit. Embodiments of the technologydisclosed herein allow a driver to program a vehicle to travel at aspeed set relative to the speed limit. The disclosed technology may beapplied to autonomous and semi-autonomous vehicles, as well as tovehicles operated by manual driving with cruise control.

In some embodiments, the driver may set a universal offset to be appliedto all speed limits. In other embodiments, the driver may set adifferent offset for different speed limits. That is, the driver maypopulate a speed map that contains different offsets to be applied todifferent determined speed limits. For instance, the driver might enteran offset of 10 mph for a speed limit of 30 mph and an offset of 5 mphfor 70 mph. To set the vehicle speed, the system applies these offsetsand may be configured to interpolate at speeds in between those forwhich an offset is defined.

In some embodiments, the system may learn a speed map from the driver'sbehaviors. For example, if the driver drives 78 when the speed limit is70 but exactly 25 when the speed limit is 25, the system may learn thisand modify the speed map accordingly. Such learning may further takeinto account features beyond speed limits, such as road type, trafficdensity, time of day, etc.

An example vehicle 102 in which embodiments of the disclosed technologymay be implemented is illustrated in FIG. 1. The vehicle depicted inFIG. 1 is a hybrid electric vehicle. However, the disclosed technologyis independent of the means of propulsion of the vehicle, and so appliesequally to vehicles without an electric motor, and to vehicles withoutan internal combustion engine.

FIG. 1 illustrates a drive system of a vehicle 102 that may include aninternal combustion engine 110 and one or more electric motors 106(which may also serve as generators) as sources of motive power. Drivingforce generated by the internal combustion engine 110 and motor 106 canbe transmitted to one or more wheels 34 via a torque converter 16, atransmission 18, a differential gear device 28, and a pair of axles 30.

As an HEV, vehicle 102 may be driven/powered with either or both ofengine 110 and the motor(s) 106 as the drive source for travel. Forexample, a first travel mode may be an engine-only travel mode that onlyuses internal combustion engine 110 as the drive source for travel. Asecond travel mode may be an EV travel mode that only uses the motor(s)106 as the drive source for travel. A third travel mode may be an HEVtravel mode that uses engine 110 and the motor(s) 106 as drive sourcesfor travel. In the engine-only and HEV travel modes, vehicle 102 relieson the motive force generated at least by internal combustion engine110, and a clutch 15 may be included to engage engine 110. In the EVtravel mode, vehicle 102 is powered by the motive force generated bymotor 106 while engine 110 may be stopped and clutch 15 disengaged.

Engine 110 can be an internal combustion engine such as a spark ignition(SI) engine (e.g., gasoline engine) a compression ignition (CI) engine(e.g., diesel engine) or similarly powered engine (whetherreciprocating, rotary, continuous combustion or otherwise) in which fuelis injected into and combusted to provide motive power. A cooling system112 can be provided to cool the engine such as, for example, by removingexcess heat from engine 110. For example, cooling system 112 can beimplemented to include a radiator, a water pump and a series of coolingchannels. In operation, the water pump circulates coolant through theengine to absorb excess heat from the engine. The heated coolant iscirculated through the radiator to remove heat from the coolant, and thecold coolant can then be recirculated through the engine. A fan may alsobe included to increase the cooling capacity of the radiator. The waterpump, and in some instances the fan, may operate via a direct orindirect coupling to the driveshaft of engine 110. In otherapplications, either or both the water pump and the fan may be operatedby electric current such as from battery 104.

An output control circuit 14A may be provided to control drive (outputtorque) of engine 110. Output control circuit 14A may include a throttleactuator to control an electronic throttle valve that controls fuelinjection, an ignition device that controls ignition timing, and thelike. Output control circuit 14A may execute output control of engine110 according to a command control signal(s) supplied from an electroniccontrol unit 50, described below. Such output control can include, forexample, throttle control, fuel injection control, and ignition timingcontrol.

Motor 106 can also be used to provide motive power in vehicle 102, andis powered electrically via a battery 104. Battery 104 may beimplemented as one or more batteries or other power storage devicesincluding, for example, lead-acid batteries, lithium ion batteries,capacitive storage devices, and so on. Battery 104 may be charged by abattery charger 108 that receives energy from internal combustion engine110. For example, an alternator or generator may be coupled directly orindirectly to a drive shaft of internal combustion engine 110 togenerate an electrical current as a result of the operation of internalcombustion engine 110. A clutch can be included to engage/disengage thebattery charger 108. Battery 104 may also be charged by motor 106 suchas, for example, by regenerative braking or by coasting during whichtime motor 106 operate as generator.

Motor 106 can be powered by battery 104 to generate a motive force tomove the vehicle and adjust vehicle speed. Motor 106 can also functionas a generator to generate electrical power such as, for example, whencoasting or braking. Battery 104 may also be used to power otherelectrical or electronic systems in the vehicle. Motor 106 may beconnected to battery 104 via an inverter 42. Battery 104 can include,for example, one or more batteries, capacitive storage units, or otherstorage reservoirs suitable for storing electrical energy that can beused to power motor 106. When battery 104 is implemented using one ormore batteries, the batteries can include, for example, nickel metalhydride batteries, lithium ion batteries, lead acid batteries, nickelcadmium batteries, lithium ion polymer batteries, and other types ofbatteries.

An electronic control unit 50 (described below) may be included and maycontrol the electric drive components of the vehicle as well as othervehicle components. For example, electronic control unit 50 may controlinverter 42, adjust driving current supplied to motor 106, and adjustthe current received from motor 106 during regenerative coasting andbreaking. As a more particular example, output torque of the motor 106can be increased or decreased by electronic control unit 50 through theinverter 42.

A torque converter 16 can be included to control the application ofpower from engine 110 and motor 106 to transmission 18. Torque converter16 can include a viscous fluid coupling that transfers rotational powerfrom the motive power source to the driveshaft via the transmission.Torque converter 16 can include a conventional torque converter or alockup torque converter. In other embodiments, a mechanical clutch canbe used in place of torque converter 16.

Clutch 15 can be included to engage and disengage engine 110 from thedrivetrain of the vehicle. In the illustrated example, a crankshaft 32,which is an output member of engine 110, may be selectively coupled tothe motor 106 and torque converter 16 via clutch 15. Clutch 15 can beimplemented as, for example, a multiple disc type hydraulic frictionalengagement device whose engagement is controlled by an actuator such asa hydraulic actuator. Clutch 15 may be controlled such that itsengagement state is complete engagement, slip engagement, and completedisengagement complete disengagement, depending on the pressure appliedto the clutch. For example, a torque capacity of clutch 15 may becontrolled according to the hydraulic pressure supplied from a hydrauliccontrol circuit (not illustrated). When clutch 15 is engaged, powertransmission is provided in the power transmission path between thecrankshaft 32 and torque converter 16. On the other hand, when clutch 15is disengaged, motive power from engine 110 is not delivered to thetorque converter 16. In a slip engagement state, clutch 15 is engaged,and motive power is provided to torque converter 16 according to atorque capacity (transmission torque) of the clutch 15.

As alluded to above, vehicle 102 may include an electronic control unit50. Electronic control unit 50 may include circuitry to control variousaspects of the vehicle operation. Electronic control unit 50 mayinclude, for example, a microcomputer that includes a one or moreprocessing units (e.g., microprocessors), memory storage (e.g., RAM,ROM, etc.), and I/O devices. The processing units of electronic controlunit 50, execute instructions stored in memory to control one or moreelectrical systems or subsystems in the vehicle. Electronic control unit50 can include a plurality of electronic control units such as, forexample, an electronic engine control module, a powertrain controlmodule, a transmission control module, a suspension control module, abody control module, and so on. As a further example, electronic controlunits can be included to control systems and functions such as doors anddoor locking, lighting, human-machine interfaces, cruise control,telematics, braking systems (e.g., ABS or ESC), battery managementsystems, and so on. These various control units can be implemented usingtwo or more separate electronic control units, or using a singleelectronic control unit.

In the example illustrated in FIG. 1, electronic control unit 50receives information from a plurality of sensors included in vehicle102. For example, electronic control unit 50 may receive signals thatindicate vehicle operating conditions or characteristics, or signalsthat can be used to derive vehicle operating conditions orcharacteristics. These may include, but are not limited to acceleratoroperation amount, A_(CC), a revolution speed, N_(E), of internalcombustion engine 110 (engine RPM), a rotational speed, N_(MG), of themotor 106 (motor rotational speed), and vehicle speed, N_(V). These mayalso include torque converter 16 output, N_(T) (e.g., output ampsindicative of motor output), brake operation amount/pressure, B, batterySOC (i.e., the charged amount for battery 104 detected by an SOCsensor). Accordingly, vehicle 102 can include a plurality of sensors 116that can be used to detect various conditions internal or external tothe vehicle and provide sensed conditions to engine control unit 50(which, again, may be implemented as one or a plurality of individualcontrol circuits). In one embodiment, sensors 116 may be included todetect one or more conditions directly or indirectly such as, forexample, fuel efficiency, E_(F), motor efficiency, E_(MG), hybrid(internal combustion engine 110+MG 12) efficiency, etc.

In some embodiments, one or more of the sensors 116 may include theirown processing capability to compute the results for additionalinformation that can be provided to electronic control unit 50. In otherembodiments, one or more sensors may be data-gathering-only sensors thatprovide only raw data to electronic control unit 50. In furtherembodiments, hybrid sensors may be included that provide a combinationof raw data and processed data to electronic control unit 50. Sensors116 may provide an analog output or a digital output.

Sensors 116 may be included to detect not only vehicle conditions butalso to detect external conditions as well. Sensors that might be usedto detect external conditions can include, for example, sonar, radar,lidar or other vehicle proximity sensors, and cameras or other imagesensors. Image sensors can be used to detect, for example, traffic signsindicating a current speed limit, road curvature, obstacles, and so on.Still other sensors may include those that can detect road grade. Whilesome sensors can be used to actively detect passive environmentalobjects, other sensors can be included and used to detect active objectssuch as those objects used to implement smart roadways that may activelytransmit and/or receive data or other information.

FIG. 2 illustrates an example architecture for controlling the speed ofa vehicle in accordance with one embodiment of the systems and methodsdescribed herein. Referring now to FIG. 2, in this example, a vehiclespeed control system 200 includes a speed control circuit 250, aplurality of sensors 116, and a plurality of vehicle systems 158.Sensors 116 and vehicle systems 158 can communicate with speed controlcircuit 250 via a wired or wireless communication interface. Althoughsensors 116 and vehicle systems 158 are depicted as communicating withspeed control circuit 250, they can also communicate with each other aswell as with other vehicle systems. Speed control circuit 250 can beimplemented as an ECU or as part of an ECU such as, for exampleelectronic control unit 50. In other embodiments, speed control circuit250 can be implemented independently of the ECU. In further embodiments,speed control circuit 250 can be implemented as part of vehicle speedsystem 274.

Speed control circuit 250 in this example includes a communicationcircuit 201, a processing circuit 203 (including a processor 206 andmemory 208 in this example) and a power supply 212. Components of speedcontrol circuit 250 are illustrated as communicating with each other viaa data bus, although other communication interfaces can be included.Speed control circuit 250 in this example also includes a speed control205 that can be operated by the user to control the speed controlcircuit 250, for example by manual controls, touch screen, voice, andthe like.

Processor 206 can include a GPU, CPU, microprocessor, or any othersuitable processing system. The memory 208 may include one or morevarious forms of memory or data storage (e.g., flash, RAM, etc.) thatmay be used to store the calibration parameters, images (analysis orhistoric), point parameters, instructions and variables for processor206 as well as any other suitable information. Memory 208 can be made upof one or more modules of one or more different types of memory, and maybe configured to store data and other information as well as operationalinstructions that may be used by the processor 206 to speed controlcircuit 250.

Although the example of FIG. 2 is illustrated using processor and memorycircuitry, as described below with reference to circuits disclosedherein, speed control circuit 250 can be implemented utilizing any formof circuitry including, for example, hardware, software, or acombination thereof. By way of further example, one or more processors,controllers, ASICs, PLAs, PALs, CPLDs, FPGAs, logical components,software routines or other mechanisms might be implemented to make up aspeed control circuit 250.

Communication circuit 201 may include either or both a wirelesstransceiver circuit 202 with an associated antenna 214 and a wired I/Ointerface 204 with an associated hardwired data port (not illustrated).As this example illustrates, communications with speed control circuit250 can include either or both wired and wireless communicationscircuits 201. Wireless transceiver circuit 202 can include a transmitterand a receiver (not shown) to allow wireless communications via any of anumber of communication protocols such as, for example, WiFi, Bluetooth,near field communications (NFC), Zigbee, and any of a number of otherwireless communication protocols whether standardized, proprietary,open, point-to-point, networked or otherwise. Antenna 214 is coupled towireless transceiver circuit 202 and is used by wireless transceivercircuit 202 to transmit radio signals wirelessly to wireless equipmentwith which it is connected and to receive radio signals as well. TheseRF signals can include information of almost any sort that is sent orreceived by speed control circuit 250 to/from other entities such assensors 116 and vehicle systems 158.

Wired I/O interface 204 can include a transmitter and a receiver (notshown) for hardwired communications with other devices. For example,wired I/O interface 204 can provide a hardwired interface to othercomponents, including sensors 116 and vehicle systems 158. Wired I/Ointerface 204 can communicate with other devices using Ethernet or anyof a number of other wired communication protocols whether standardized,proprietary, open, point-to-point, networked or otherwise.

Power supply 212 can include one or more of a battery or batteries (suchas, e.g., lithium-ion, lithium-polymer, nickel metal hydride (NiMH),nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-hydrogen (NiH₂),rechargeable, primary battery, etc.), a power connector (e.g., toconnect to vehicle-supplied power, etc.), an energy harvester (e.g.,solar cells, piezoelectric system, etc.), or include any other suitablepower supply.

Sensors 116 may include additional sensors that may or not otherwise beincluded on a standard vehicle 102 with which the speed control system200 is implemented. In the illustrated example, sensors 116 includevehicle speed sensor 222, image sensor 224, road sensor 226, weathersensor 228, and clock 230. Additional sensors 232 can also be includedas may be appropriate for a given implementation of speed control system200. Image sensor 224 can be implemented as a CCD, LCD or other imagesensor to detect road signs, road conditions, obstacles in the road,etc. Sensor information can be processed (e.g., via processing circuit203) to determine a current speed limit (e.g., via road signs), a typeand severity of adverse road conditions, and so on. Road sensors 226 caninclude, for example, radar and lidar sensors to detect road contoursand terrain, wheel-mounted accelerometers to detect wheel deflectionamounts, chassis-mounted accelerometers to detect vibration amounts, andso on. Weather sensors 228 can include temperature, pressure andhumidity sensors such as, for example, to detect freezing conditions.

Vehicle systems 158 can include any of a number of different vehiclecomponents or subsystems used to control or monitor various aspects ofthe vehicle and its performance. In this example, the vehicle systems158 include a vehicle position system 272, a vehicle speed system 274,and other vehicle systems 282. Vehicle position system 272 may determinea geographic position of the vehicle, as well as its direction andspeed. Vehicle position system 272 may include a global positioningsatellite (GPS) system or the like. The vehicle speed system 274 mayinclude systems such as acceleration systems, braking systems, and thelike.

During operation, speed control circuit 250 can receive information fromvarious vehicle sensors 116 to determine whether the speed control modeshould be activated. Also, the driver may manually activate the speedcontrol mode by operating speed control 205. Communication circuit 201can be used to transmit and receive information between speed controlcircuit 250 and sensors 116, and speed control circuit 250 and vehiclesystems 158. Also, sensors 116 may communicate with vehicle systems 158directly or indirectly (e.g., via communication circuit 201 orotherwise).

In various embodiments, communication circuit 201 can be configured toreceive data and other information from sensors 116 that is used indetermining whether to activate the speed control mode. Additionally,communication circuit 201 can be used to send an activation signal orother activation information to various vehicle systems 158 as part ofentering the speed control mode. For example, as described in moredetail below, communication circuit 201 can be used to send signals to,for example, the vehicle speed system 274. Examples of this aredescribed in more detail below.

FIG. 3 is a flowchart illustrating a process 300 for controlling thespeed of a vehicle using offset speeds according to one embodiment.Referring to FIG. 3, the process 300 begins, at 302. The speed controlcircuit 250 first determines whether the speed control mode is on, at304. This may include determining whether the speed control mode hasbeen activated, for example manually by the driver using the speedcontrol 205. The speed control circuit 250 continues this determinationuntil the speed control mode is activated.

When the speed control mode is activated, the speed control circuit 250determines a speed limit for the section of road being traveled by thevehicle, at 306. In some embodiments, the speed control circuit 250determines the speed limit using images of road signs captured by theimage sensor 224. In other embodiments, the speed control circuit 250determines the speed limit using databases that correlate the positionof the vehicle with the speed limit. In yet further embodiments, thespeed limit may be included in information received from vehiclepositioning system 272. After determining the speed limit, the speedcontrol circuit 250 determines an offset from the determined speedlimit. For example, in some embodiments the offset can be determinedfrom a speed map containing offset information relative to thedetermined speed limit, at 308.

FIG. 4 shows an example speed map 400 storing offset speeds according toone embodiment. Referring to FIG. 4, the speed map 400 includes aplurality of entries. Each entry associates an offset value with arespective speed limit. In the speed map 400 and FIG. 4, an offset of 5mph is associated with speed limits of 5 mph, 10 mph, and 70 mph, whilean offset of 10 mph is associated with the speed limit of 30 mph. Insome embodiments, the speed map 400 is populated manually by the user.For example, the user may employ an application (e.g., a smart phoneapp) or the vehicle touch panel to populate the speed map 400 byentering his or her desired offset amounts for one or more of theplurality of speed limits. As another example, the driver may employ thespeed control 205 to enter or modify entries in speed map 400. Forexample, while driving at 40 mph in a 30 mph zone, the user may press aspeed control button that records both the speed limit of 30 mph and theassociated offset of 10 mph in the speed map 400. In an exampledescribed below, speed map 400 may be populated by machine learningthrough observation of the speeds driven in different speed limit zones.In some embodiments, multiple speed maps are maintained, one for eachdriver of the vehicle for example, as described above.

The speed control circuit 250 determines an offset value based on (i)the speed limit, and (ii) the speed map 400. The speed control circuit250 then sets the speed of the vehicle according to the speed limit andthe determined offset value, at 310. In particular, the speed controlcircuit 250 determines a desired vehicle speed by adding the offsetvalue to the determined speed limit. For example, referring to FIG. 4,for a speed limit of 30 mph, the offset is 10 mph, yielding a desiredspeed of 40 mph. Therefore, the speed control circuit 250 sets the speedof the vehicle to 40 mph. When the speed map 400 does not contain anentry for the determined speed limit, speed control circuit 250 mayinterpolate using a plurality of the entries in the speed map 400. Inother embodiments, when the speed map 400 does not contain an entry forthe determined speed limit, the vehicle set speed can be the same as thedetermined speed limit.

The speed control circuit 250 may be implemented to occasionallydetermine whether the speed control mode has been deactivated, at 312.While the speed control mode is active, the speed control circuit 250continues to determine the speed limit, get offsets from the speed map,and set the vehicle speed according to the speed limits and offsets.When the speed control mode is deactivated, the process 300 ends, at314. In some embodiments, the driver may manually deactivate the speedcontrol mode. In other embodiments, the vehicle may automaticallydeactivate the speed control mode such as, for example, for safetyreasons.

In some embodiments, the speed map stores desired speeds rather thanoffsets. FIG. 5 is a flowchart illustrating a process 500 forcontrolling the speed of a vehicle using desired speeds according to oneembodiment. Referring to FIG. 5, the process 500 begins, at 502. Thespeed control circuit 250 first determines whether the speed controlmode is on, at 504. This may include determining whether the speedcontrol mode has been activated, for example manually by the driverusing the speed control 205. The speed control circuit 250 continuesthis determination until the speed control mode is activated.

When the speed control mode is entered, the speed control circuit 250determines a speed limit, at 506, for example as described above. Afterdetermining the speed limit, the speed control circuit 250 gets adesired speed from a speed map based on the determined speed limit, at508.

FIG. 6 shows an example speed map 600 storing desired speeds accordingto one embodiment. Referring to FIG. 6, the speed map 600 includes aplurality of entries. Each entry associates a desired speed with arespective speed limit. In the speed map 600 and FIG. 6, desired speedsof 10 mph, 15 mph, 40 mph, and 75 mph are associated with speed limitsof 5 mph, 10 mph, 30 mph, and 70 mph, respectively. In some embodiments,the speed map 600 is populated manually by the user. For example, theuser may employ an application (e.g., a smart phone app) or the vehicletouch panel to populate the speed map 600 by entering his or her travelspeeds for one or more of the plurality of speed limits. As anotherexample, the driver may employ the speed control 205 to enter or modifyentries in speed map 600. For example, while driving at 60 mph in a 50mph zone, the user may press a speed control button that records boththe speed limit of 50 mph and the associated desired speed of 60 mph inthe speed map 600. As noted above, speed map 600 may be populated bymachine learning through observation of the speeds driven in differentspeed limit zones. In some embodiments, multiple speed maps aremaintained, one for each driver of the vehicle, for example as describedabove.

Referring again to FIG. 5, the speed control circuit 250 determines adesired speed based on (i) the speed limit, and (ii) the speed map 600.The speed control circuit 250 then sets the speed of the vehicleaccording to the determined desired speed, at 510. For example,referring to FIG. 6, for a speed limit of 30 mph, the desired speed is40 mph. Therefore the speed control circuit 250 sets the speed of thevehicle to 40 mph. When the speed map 600 does not contain an entry forthe determined speed limit, speed control circuit 250 may interpolateusing a plurality of the entries in the speed map 600.

The speed control circuit 250 occasionally determines whether the speedcontrol mode has been deactivated, at 512. While the speed control modeis active, the speed control circuit 250 continues to determine speedlimits, get desired speeds from the speed map, and set the vehicle speedto the desired speed. When the speed control mode is deactivated, theprocess 500 ends, at 514.

In some embodiments, the speed maps described herein are populatedwithout user intervention, such as through machine learning. In suchembodiments, the speed control circuit 250 observes the speeds driven invarious speed limit zones and populates the speed maps accordingly. FIG.7 is a flowchart illustrating a process 700 for learning a speed mapaccording to one embodiment. Referring to FIG. 7, the process 700begins, at 702. The speed control circuit 250 first determines whetherthe speed control learning mode is on, at 704. This may includedetermining whether the speed control learning mode has been activated,for example manually by the driver using the speed control 205. Thespeed control circuit 250 continues this determination until the speedcontrol learning mode is activated. In other embodiments, the speedcontrol learning mode can always be on such that it is constantlyadapting to the driver's behavior.

When the speed control learning mode is entered, the speed controlcircuit 250 determines a speed limit, at 706, for example as describedabove regarding speed control. After determining the speed limit, thespeed control circuit 250 measures the speed of the vehicle, at 708. Thespeed control circuit 250 then records the speed limit and vehicle speedin the speed map, at 710. For a speed map using offsets, the speedcontrol circuit 250 records the speed limit and the offset in the speedmap. For a speed map using desired speeds, the speed control circuit 250records the speed limit and the desired speed in the speed map.

The speed control circuit 250 occasionally determines whether the speedcontrol learning mode has been deactivated, at 712. While the speedcontrol learning mode is active, the speed control circuit 250 continuesto determine the speed limit, measure the vehicle speed, and populatethe speed map. When the speed control learning mode is deactivated, theprocess 700 ends, at 714.

In some embodiments, the speed control circuit 250 also considersadverse conditions when setting the vehicle speed. For example, sensors116 may determine an adverse condition for the road being traveled bythe vehicle. Adverse road conditions may be determined when the road isdetected to be wet, icy, rough, winding, and the like. Other adverseconditions may be considered as well, for example including trafficdensity, time of day, and the presence of special zones such as schoolzones and construction zones.

In some embodiments, particular adverse-conditions offsets or desiredspeeds may be recorded in the speed map. FIG. 8 shows a speed map 800using adverse-conditions offsets. Speed map 800 includes a separatecolumn including adverse-conditions offsets for different speed limits.In embodiments using such a speed map, when adverse conditions aredetermined, the speed control circuit 250 uses the adverse-conditionsoffsets instead of the normal offsets. In other embodiments the speedmap may specify adverse conditions desired speeds rather than offsets.Various sensors 116 can be used to determine whether an adversecondition exists, and if so, the type of adverse condition. For example,road sensors 226 may determine the presence of potholes or other adverseroad conditions that may warrant a lower or a negative offset. Asanother example, a combination of weather, image and road sensors may beused to determine whether ice, snow or other conditions have led toslippery road conditions.

For speed maps using offsets, the offsets for adverse conditionscompared to the normal offsets are generally smaller, zero, or evennegative numbers. Referring again to FIG. 8, for speed limits of 5 mph,10 mph, 30 mph, and 70 mph, while the normal offsets are 5 mph, 5 mph,10 mph, and 5 mph, respectively, the offsets for adverse conditions are0 mph, 0 mph, −5 mph, and −10 mph, respectively. So for a speed limit of70 mph, the normal desired speed would be 75 mph, where the desiredspeed under adverse conditions would be 60 mph.

In some embodiments, different offsets are used for different adverseconditions. So for a particular speed limit, the offset for a schoolzone might be 0 mph, while the offset for an icy road might be −15 mph.As with normal offset values, adverse-conditions offsets can be manuallyentered by a driver or learned based on actual driver behavior. Thespeed settings for adverse-conditions can be provided asadverse-conditions offsets (as shown in FIG. 8), or as actualadverse-conditions speeds.

In some embodiments, adverse-conditions speed settings can be factoryset or factory-established not-to-exceed limits, and can be imposed suchthat the offsets used during detected adverse-conditions cannot exceed apredetermined amount. In further embodiments, an adverse-conditionssetting can be employed such that the speed offset feature is canceledupon the detection of certain adverse-conditions.

As indicated above, in various embodiments the offset amounts or desiredspeeds can be determined for individual drivers of the vehicle. Forexample, in accordance with the examples provided above, various driversof a vehicle may manually enter their desired offset amounts or thevehicle can employ machine learning or other techniques to populate aspeed map based on observed driver behavior. The vehicle can use variousdriver identification techniques to determine an identity of the driverof the vehicle and to apply the speed map that is particular to theidentified driver. For example, the vehicle can employ various biometricsensors to determine the identity of the driver. These can include, forexample, image sensors for facial recognition, voice recognition,fingerprint sensors, and so on. As another example, a set of offsetamounts can be correlated to a smart key used to operate the vehicle. Asyet another example, a driver may be asked to enter his or heridentification into the vehicle head units such as via keypad entry orspeech recognition.

As used herein, the term component might describe a given unit offunctionality that can be performed in accordance with one or moreembodiments of the present application. As used herein, a componentmight be implemented utilizing any form of hardware, software, or acombination thereof. For example, one or more processors, controllers,ASICs, PLAs, PALs, CPLDs, FPGAs, logical components, software routinesor other mechanisms might be implemented to make up a component. Variouscomponents described herein may be implemented as discrete components ordescribed functions and features can be shared in part or in total amongone or more components. In other words, as would be apparent to one ofordinary skill in the art after reading this description, the variousfeatures and functionality described herein may be implemented in anygiven application. They can be implemented in one or more separate orshared components in various combinations and permutations. Althoughvarious features or functional elements may be individually described orclaimed as separate components, it should be understood that thesefeatures/functionality can be shared among one or more common softwareand hardware elements. Such a description shall not require or implythat separate hardware or software components are used to implement suchfeatures or functionality.

Where components are implemented in whole or in part using software,these software elements can be implemented to operate with a computingor processing component capable of carrying out the functionalitydescribed with respect thereto. One such example computing component isshown in FIG. 9. Various embodiments are described in terms of thisexample-computing component 900. After reading this description, it willbecome apparent to a person skilled in the relevant art how to implementthe application using other computing components or architectures.

Referring now to FIG. 9, computing component 900 may represent, forexample, computing or processing capabilities found within aself-adjusting display, desktop, laptop, notebook, and tablet computers.They may be found in hand-held computing devices (tablets, PDA's, smartphones, cell phones, palmtops, etc.). They may be found in workstationsor other devices with displays, servers, or any other type ofspecial-purpose or general-purpose computing devices as may be desirableor appropriate for a given application or environment. Computingcomponent 900 might also represent computing capabilities embeddedwithin or otherwise available to a given device. For example, acomputing component might be found in other electronic devices such as,for example, portable computing devices, and other electronic devicesthat might include some form of processing capability.

Computing component 900 might include, for example, one or moreprocessors, controllers, control components, or other processingdevices. This can include a processor, and/or any one or more of thecomponents making up hybrid vehicle 102 and its component parts, forexample such as the computing component. Processor 904 might beimplemented using a general-purpose or special-purpose processing enginesuch as, for example, a microprocessor, controller, or other controllogic. Processor 904 may be connected to a bus 902. However, anycommunication medium can be used to facilitate interaction with othercomponents of computing component 900 or to communicate externally.

Computing component 900 might also include one or more memorycomponents, simply referred to herein as main memory 908. For example,random access memory (RAM) or other dynamic memory, might be used forstoring information and instructions to be executed by processor 904.Main memory 908 might also be used for storing temporary variables orother intermediate information during execution of instructions to beexecuted by processor 904. Computing component 900 might likewiseinclude a read only memory (“ROM”) or other static storage devicecoupled to bus 902 for storing static information and instructions forprocessor 904.

The computing component 900 might also include one or more various formsof information storage mechanism 910, which might include, for example,a media drive 912 and a storage unit interface 920. The media drive 912might include a drive or other mechanism to support fixed or removablestorage media 914. For example, a hard disk drive, a solid state drive,a magnetic tape drive, an optical drive, a compact disc (CD) or digitalvideo disc (DVD) drive (R or RW), or other removable or fixed mediadrive might be provided. Storage media 914 might include, for example, ahard disk, an integrated circuit assembly, magnetic tape, cartridge,optical disk, a CD or DVD. Storage media 914 may be any other fixed orremovable medium that is read by, written to or accessed by media drive912. As these examples illustrate, the storage media 914 can include acomputer usable storage medium having stored therein computer softwareor data.

In alternative embodiments, information storage mechanism 910 mightinclude other similar instrumentalities for allowing computer programsor other instructions or data to be loaded into computing component 900.Such instrumentalities might include, for example, a fixed or removablestorage unit 922 and an interface 920. Examples of such storage units922 and interfaces 920 can include a program cartridge and cartridgeinterface, a removable memory (for example, a flash memory or otherremovable memory component) and memory slot. Other examples may includea PCMCIA slot and card, and other fixed or removable storage units 922and interfaces 920 that allow software and data to be transferred fromstorage unit 922 to computing component 900.

Computing component 900 might also include a communications interface924. Communications interface 924 might be used to allow software anddata to be transferred between computing component 900 and externaldevices. Examples of communications interface 924 might include a modemor softmodem, a network interface (such as an Ethernet, networkinterface card, WiMedia, IEEE 802.XX or other interface). Other examplesinclude a communications port (such as for example, a USB port, IR port,RS232 port Bluetooth® interface, or other port), or other communicationsinterface. Software/data transferred via communications interface 924may be carried on signals, which can be electronic, electromagnetic(which includes optical) or other signals capable of being exchanged bya given communications interface 924. These signals might be provided tocommunications interface 924 via a channel 928. Channel 928 might carrysignals and might be implemented using a wired or wireless communicationmedium. Some examples of a channel might include a phone line, acellular link, an RF link, an optical link, a network interface, a localor wide area network, and other wired or wireless communicationschannels.

In this document, the terms “machine-readable storage medium,” “computerprogram medium,” and “computer usable medium” are used to generallyrefer to transitory or non-transitory media. Such media may be, e.g.,memory 908, storage unit 920, media 914, and channel 928. These andother various forms of computer program media or computer usable mediamay be involved in carrying one or more sequences of one or moreinstructions to a processing device for execution. Such instructionsembodied on the medium, are generally referred to as “computer programcode” or a “computer program product” (which may be grouped in the formof computer programs or other groupings). When executed, suchinstructions might enable the computing component 900 to performfeatures or functions of the present application as discussed herein.

It should be understood that the various features, aspects andfunctionality described in one or more of the individual embodiments arenot limited in their applicability to the particular embodiment withwhich they are described. Instead, they can be applied, alone or invarious combinations, to one or more other embodiments, whether or notsuch embodiments are described and whether or not such features arepresented as being a part of a described embodiment. Thus, the breadthand scope of the present application should not be limited by any of theabove-described exemplary embodiments.

Terms and phrases used in this document, and variations thereof, unlessotherwise expressly stated, should be construed as open ended as opposedto limiting. As examples of the foregoing, the term “including” shouldbe read as meaning “including, without limitation” or the like. The term“example” is used to provide exemplary instances of the item indiscussion, not an exhaustive or limiting list thereof. The terms “a” or“an” should be read as meaning “at least one,” “one or more” or thelike; and adjectives such as “conventional,” “traditional,” “normal,”“standard,” “known.” Terms of similar meaning should not be construed aslimiting the item described to a given time period or to an itemavailable as of a given time. Instead, they should be read to encompassconventional, traditional, normal, or standard technologies that may beavailable or known now or at any time in the future. Where this documentrefers to technologies that would be apparent or known to one ofordinary skill in the art, such technologies encompass those apparent orknown to the skilled artisan now or at any time in the future.

The presence of broadening words and phrases such as “one or more,” “atleast,” “but not limited to” or other like phrases in some instancesshall not be read to mean that the narrower case is intended or requiredin instances where such broadening phrases may be absent. The use of theterm “component” does not imply that the aspects or functionalitydescribed or claimed as part of the component are all configured in acommon package. Indeed, any or all of the various aspects of acomponent, whether control logic or other components, can be combined ina single package or separately maintained and can further be distributedin multiple groupings or packages or across multiple locations.

Additionally, the various embodiments set forth herein are described interms of exemplary block diagrams, flow charts and other illustrations.As will become apparent to one of ordinary skill in the art afterreading this document, the illustrated embodiments and their variousalternatives can be implemented without confinement to the illustratedexamples. For example, block diagrams and their accompanying descriptionshould not be construed as mandating a particular architecture orconfiguration.

What is claimed is:
 1. A method for automatically controlling the speedof a vehicle, the method comprising: determining a speed limit;determining an offset value that relies on at least one ofdriver-defined offset values and learned driver behaviors when operatingthe vehicle by referencing a speed map that is generated with the use ofat least one of geographic speed limits and learned driver behaviors,the speed map comprising a plurality of entries, each entry associatingone of the offset values with a respective speed limit; andautomatically setting the speed of the vehicle according to the speedlimit and the determined offset value.
 2. The method of claim 1, furthercomprising: modifying the speed map according to behavior of a driver ofthe vehicle.
 3. The method of claim 2, wherein: modifying the speed mapoccurs without human intervention.
 4. The method of claim 2, wherein:modifying the speed map occurs responsive to human intervention.
 5. Themethod of claim 2, wherein modifying the speed map comprises: measuringa speed of the vehicle; and recording the speed limit and an offsetvalue in the speed map, the offset value representing a differencebetween the speed of the vehicle and the speed limit.
 6. The method ofclaim 1, further comprising: determining an adverse condition for theroad being traveled by the vehicle; and adjusting the speed of thevehicle based on the adverse condition.
 7. The method of claim 1,wherein determining an offset value comprises: when the speed map doesnot contain an entry for the determined speed limit, interpolating usinga plurality of the entries in the speed map.
 8. A method forautomatically controlling the speed of a vehicle, the method comprising:determining a speed limit; determining a desired speed based on at leastone of driver-defined desired speeds and learned driver behaviors whenoperating the vehicle by referencing a speed map, the speed mapcomprising a plurality of entries, each entry associating one of thedesired speeds with a respective speed limit; and automatically settingthe speed of the vehicle according to the speed limit, desired speed,and an offset value, wherein the offset value is determined bydriver-defined offset values and learned driver behaviors.
 9. The methodof claim 8, further comprising: modifying the speed map according tobehavior of a driver of the vehicle.
 10. The method of claim 9, wherein:modifying the speed map occurs without human intervention.
 11. Themethod of claim 9, wherein: modifying the speed map occurs responsive tohuman intervention.
 12. The method of claim 9, wherein modifying thespeed map comprises: measuring a speed of the vehicle; and recording thespeed of the vehicle and the speed limit in the speed map.
 13. Themethod of claim 8, further comprising: determining an adverse conditionfor the road being traveled by the vehicle; and adjusting the speed ofthe vehicle based on the adverse condition.
 14. The method of claim 9,wherein determining a desired speed comprises: when the speed map doesnot contain an entry for the determined speed limit, interpolating usinga plurality of the entries in the speed map.
 15. A non-transitorymachine-readable storage medium encoded with instructions executable bya hardware processor of a computing component of a vehicle, themachine-readable storage medium comprising instructions to cause thehardware processor to: determine a speed limit; determine an offsetvalue that relies on at least one of driver-defined offset values andlearned driver behaviors when operating the vehicle by referencing aspeed map that is generated with the use of at least one of geographicspeed limits and learned driver behaviors, the speed map comprising aplurality of entries, each entry associating one of the offset valueswith a respective speed limit; and automatically set the speed of thevehicle according to the speed limit and the determined offset value.16. The non-transitory machine-readable storage medium of claim 15,further comprising instructions to cause the hardware processor to:modify the speed map according to behavior of a driver of the vehicle.17. The non-transitory machine-readable storage medium of claim 16,further comprising instructions to cause the hardware processor to:modify the speed map without human intervention.
 18. The non-transitorymachine-readable storage medium of claim 16, further comprisinginstructions to cause the hardware processor to: modify the speed mapresponsive to human intervention.
 19. The non-transitorymachine-readable storage medium of claim 16, further comprisinginstructions to cause the hardware processor to: measure a speed of thevehicle; and record the speed limit and an offset value in the speedmap, the offset value representing a difference between the speed of thevehicle and the speed limit.
 20. The non-transitory machine-readablestorage medium of claim 15, further comprising instructions to cause thehardware processor to: determine an adverse condition for the road beingtraveled by the vehicle; and adjust the speed of the vehicle based onthe adverse condition.